Electrolysis inhibiting marine energy management system

• US 5,510,659 A
• Filed: 01/13/1994
• Issued: 04/23/1996
• Est. Priority Date: 01/13/1994
• Status: Expired due to Fees

• Current Assignee: David C. Lewis, Jonathan M. Lewis
• Original Assignee: David C. Lewis, Jonathan M. Lewis
• Inventors: Lewis, David C., Lewis, Jonathan M.
• Primary Examiner(s): Shoop, Jr., William M.
• Assistant Examiner(s): PALADINI, ALBERT WILLIAM
• Application Number:
  US08/181,185
• Time in Patent Office: 831 Days
• Field of Search: 307/10.7, 307/64, 307/66, 307/85-87, 307/11, 307/95, 320/43, 320/44, 361/139, 361/154, 361/160, 361/170
• US Class Current: 307/11
• CPC Class Codes: B63J 2003/043 using shore connectors for electric power supply from shore-borne mains, or other electric energy sources external to the vessel, e.g. for docked, or moored vessels
• CPC Class Codes: H02J 2310/42 for ships or vessels
• CPC Class Codes: H02J 4/00 Circuit arrangements for mains or distribution networks not specified as ac or dc
• CPC Class Codes: H02J 7/0045 concerning the insertion or the connection of the batteries

Abstract

Supply of ac current from the marina source to the boat'"'"'s DC loads is permitted only when an isolation relay completes the electrical circuit therebetween. A control means monitor the boats battery voltage, battery charger current and DC load current, and supplies operating current to the isolation relay only when those monitored conditions indicate a need for the supply of current from the on-shore source to the boat. The duration in which the on-shore ground lead is connected to the boat'"'"'s ground system, a customary path for electrolysis currents, and corrosion damage caused by those currents, and the duration of consumption of on-shore electricity, are thus limited.

Claims

1. In a marine electrical power system for boats docked in water at a boat marina, said boat marina comprising:

an on-shore power distribution system associated with said boat marina for distributing a.c. electrical power from an on-shore source to a plurality of boat dock positions, said distribution being via a plurality of electrical leads extending dockside, said on-shore power distribution system comprising at least first and second a.c. power leads and a third ground lead; and

at least one of said docked boats, including;

rechargeable D.C. battery means for storing charge of electricity and producing a predetermined voltage when fully charged, said battery including a first polarity terminal and a second polarity terminal;

an on-board a.c. electrical distribution system, said on-board a.c. electrical distribution system, including a first lead, second lead and a third ground lead;

means for connecting said on-board a.c. electrical distribution system in circuit with said on-shore a.c. electrical distribution system;

battery charger means, said battery charger means having an input for connection to said on-board a.c. electrical distribution system and an output connected to said battery means for providing D.C. current to said D.C. battery means, responsive to a.c. power supplied at said input, said battery charger means output including a first positive polarity terminal for connection to a positive polarity terminal of said D.C. battery means and a negative polarity terminal for connection to a negative polarity terminal of said battery means and a ground lead for connection to said third ground lead;

D.C. electrical distribution system connected to said battery means, said D.C. electrical distribution system including at least a first lead connected to a first polarity terminal of said battery and a second lead connected to the second polarity terminal of said battery, whereby said output of said battery charger means also supplies D.C. current to other electrical loads connected to said D.C. electrical distribution system;

stand-by electrical load device means coupled to said D.C. distribution system, said load device means being normally in a non-current consuming standby condition, and producing a demand for current only in response to a predetermined condition on said boat requiring said load device means to produce a predetermined action, wherein said load device means draws D.C. current from said D.C. distribution system; and

a ground system, said ground system including at least some metallic fittings on said boat that extend to an external surface of the boat for contact with said dockside water;

said ground system being connected to respective ground leads associated with each of said battery charger means and said electrical load device means;

the improvement therein of a electrolysis inhibiting power management system which comprises in combination therewith;

isolation switch means associated with said docked boat connected in electrical series circuit between said on-boat a.c. electrical distribution system and said battery charger means input and on-board ground system, said isolation switch means having a plurality of inputs connected to said respective electrical leads of said on-board a.c. distribution system and a plurality of outputs connected to the respective corresponding electrical leads of said D.C. battery charger means and said on-board ground system, said switch means having a first state for interrupting a current conducting path between the respective switch inputs and outputs and an alternate a second state for completing a current conducting path between those respective inputs and outputs; and

control means associated with said docked boat for controlling operation of said isolation switch means, said control means for placing said isolation switch means in its second state, responsive to the occurrence of any of (a) a current demand by said stand-by electrical device means or (b) said battery voltage being below a predetermined minimum voltage level, whereby two of said a.c. electrical leads of said on-board a.c. distribution system are connected in operative relationship to said input of said battery charger means and said on-shore ground lead is connected to said ground system of said on-board D.C. distribution system and said battery charger means produces a D.C. current output, and for restoring said isolation switch means to its first state to thereby interrupt said connections to the on-boat a.c. distribution system and ground, responsive to at least (a) an absence of demand for current by said stand-by electrical device and said D.C. output current supplied by said battery charger means being below a predetermined minimum level for a predetermined period of time and (b) said battery voltage being at or above said predetermined level;

whereby said ground from said on-shore a.c. distribution system is connected to said boat ground system only for limited intervals during the period of time in which the boat is docked at the marina to thereby limit the duration of any corrosion causing ground currents transversing a path from the boat ground system, through the dockside water to or through other docked boats, and said on-shore ground system.

2. The invention as defined in claim 1, wherein said control means further includes:

first sensor means for monitoring said battery voltage;

second sensor means for monitoring current produced by said charger means; and

third sensor means for monitoring current drawn by said standby electrical device.

3. The invention as defined in claim 1, wherein said control means further comprises:

programmable clock means, said clock means for producing an output signal at a predetermined interval and maintaining that output for a predetermined duration;

said control means being responsive to said clock output signal for placing said isolation switch means in its second state for at least said predetermined duration.

4. The invention as defined in claim 1, further comprising:

remote control means intermediate said control means and said isolation switch means for providing transmission of control signals to said isolation switch means.

5. The invention as defined in claim 4 wherein said remote control means further comprises:

encoder transmitting means coupled to said control means for encoding control signals from said control means;

decoder receiving means coupled to said isolation switch means for receiving encoded control signals from said encoder means;

said encoder transmitting means providing a wireless transmission path to said decoder receiving means.

6. The invention as defined in claim 1, wherein said isolation switch means comprises:

an electromagnetic relay, said relay having an electromagnetic coil and at least three sets of normally open switching contacts, said contacts being switched to the closed condition responsive to application of current to said electromagnetic coil.

7. The invention as defined in claim 5, wherein said isolation switch means comprises:

an electromagnetic relay, said relay having an electromagnetic coil and at least three sets of normally open switching contacts, said contacts being switched to the closed condition responsive to application of current to said electromagnetic coil.

8. In a marine electrical power system for boats docked in water at a boat marina;

said marina comprising;

an on-shore power distribution system associated with said boat marina for distributing a.c. electrical power from an on-shore source to a plurality of boat dock positions, said distribution being via a plurality of electrical leads extending dockside, said on-shore power distribution system comprising at least first and second a.c. power leads and a third ground lead; and

a plurality of said docked boats, each including;

rechargeable D.C. battery means for storing charge of electricity and producing a predetermined voltage when fully charged, said battery including a first polarity terminal and a second polarity terminal;

an on-board a.c. electrical distribution system, said on-board a.c. electrical distribution system, including a first lead, second lead and a third ground lead;

means for connecting said on-board a.c. electrical distribution system in circuit with said on-shore a.c. electrical distribution system;

battery charger means, said battery charger means having an input for connection to said on-board a.c. electrical distribution system and an output connected to said battery means for providing D.C. current to said D.C. battery means, responsive to a.c. power supplied at said input, said battery charger means output including a first positive polarity terminal for connection to a positive polarity terminal of said D.C. battery means and a negative polarity terminal for connection to a negative polarity terminal of said battery means and a ground lead for connection to said third ground lead;

D.C. electrical distribution system connected to said battery means, said D.C. electrical distribution system including at least a first lead connected to a first polarity terminal of said battery means and a second lead connected to the second polarity terminal of said battery means, whereby said output of said battery charger means also supplies D.C. current to other electrical loads connected to said D.C. electrical distribution system;

stand-by electrical load device means coupled to said D.C. distribution system, said load device means being normally in a non-current consuming standby condition, and producing a demand for current only in response to a predetermined condition on said boat requiring said load device means to produce a predetermined action, wherein said load device means draws D.C. current from said D.C. distribution system; and

a ground system, said ground system including at least some metallic fittings on said boat that extend to an external surface of the boat for contacting said dockside water;

said ground system being connected to respective ground leads associated with, said battery charger means, and said electrical load device means;

the improvement therein of a electrolysis inhibiting power management system which comprises in combination therewith;

a plurality of isolation switch means, each said isolation switch means being associated with a corresponding one of said docked boats;

each said isolation switch means being connected in electrical series circuit between said on-boat a.c. electrical distribution system and said battery charger means input and on-board ground system of the associated boat, said isolation switch means having a plurality of inputs connected to said respective electrical leads of said on-boat a.c. distribution system and a plurality of outputs connected to the respective corresponding inputs of said battery charger means and said boat ground system, said switch means having a first state for interrupting a current conducting path between the respective inputs and outputs and an alternate a second state for completing a current conducting path between those respective inputs and outputs; and

a plurality of control means, each said control means being associated with a corresponding one of said docked boats and a corresponding one of said isolation switch means, for controlling operation of said associated one of said isolation switch means, said control means for placing said isolation switch means in its second state, responsive at least to the occurrence of any of (a) a current demand by said stand-by electrical device means or (b) said battery voltage being below a predetermined minimum voltage level on the associated boat, whereby two of said a.c. electrical leads of said on-shore a.c. distribution system are connected, via said on-board a.c. distribution system, in operative relationship to said input of said battery charger means and said on-shore ground lead is connected to said boat ground system and said battery charger means produces D.C. current, and for restoring said isolation switch means to its first state to thereby interrupt said connections to the on-shore a.c. distribution system and ground, responsive to at least (a) an absence of demand for current by said stand-by electrical device and said D.C. output current supplied by said battery charger means being below a predetermined minimum level for a predetermined period of time and (b) said battery voltage on said associated boat being at or above said predetermined level;

whereby said ground from said on-shore a.c. distribution system is connected to said boat ground system on said respective boat only for limited intervals during the period of time in which the boat is docked at the marina to thereby limit the duration of any corrosion causing ground currents transversing a path from the boat ground system, through the dockside water to or through other docked boats and said on-shore ground system.

9. The invention as defined in claim 8 wherein said isolation switch means is located on said boat marina.

10. The invention as defined in claim 8 wherein said isolation switch means is located on said boat.

11. The invention as defined in claim 8 further comprising:

remote control means for coupling said control means to said isolation switch means.

12. The invention as defined in claim 11 wherein said remote control means further comprises any of an optical remote control means, an infra-red remote control means, a sonar remote control means, a current carrier type remote control means, and a radio remote control means.

13. An electrolysis inhibiting power management system for in-water resident boats comprising:

an a.c. distribution system for connection to an on-shore a.c. distribution system, said distribution systems including a hot lead, a neutral lead and a ground lead;

battery charger means having an input for connection to said a.c. distribution system for supplying current to a DC distribution system, said DC distribution system being connected to an electrical battery and to a DC standby electrical load;

a ground system on said boat, including at least one through-hull fitting for contact with said water, with said ground system being connected to a corresponding ground connection on each of said battery charger means and said DC standby electrical load;

control means for monitoring a plurality of electrical conditions said boat, said control means including;

first current sensor means for monitoring current supplied by said battery charger means;

second current sensor means for monitoring current supplied to said DC standby electrical load; and

voltage sensor means for monitoring voltage of said electrical battery;

switching means coupled to said control means for connecting said ac distribution system to said input of said battery charger means, responsive to an output from said control means;

said control means being responsive to said sensor means for providing output to said switching means during the presence of predetermined sensed conditions, whereby said on-shore ac distribution system, including said ground lead, is connected via said on-board ac distribution system to said battery charger means and to said boat ground system only during the presence of said predetermined sensed conditions.